Method of crimping of filamentary materials

ABSTRACT

A crimping chamber is provided having an axially spaced inlet and outlet and intermediate the same radial venting ports. A filamentary material to be crimped is entrained and inserted into the inlet of the chamber with a stream of hot fluid which, upon entry into the chamber, becomes vented through the venting ports. Into the chamber in the region of the outlet there is admitted in counter-flow to the filamentary material a stream of cool gas which also subsequently vents through the outlet ports, and admitted into this stream of cool gas is a liquid to be finely dispersed therein.

United States Patent 1 1 g 1 ,802,039

Bauch Apr. 9, 1974 [5 METHOD OF CRIMPING 0F 3,727,275 4 1973 Ohayon 28/L4 FILAMENTARY MATERIALS 3,729,831 5/1973 Kosaka et al. 34/23 3,281,913 11/1966 Morehead et a] 28/7211 X [75] Inventor: Ernst Bauch, Bordesholm, Germany 3,303,54 2 1967 3,340,585 9/1967 Buckley et al. 28/7214 X [73] Asslgnee' Neumunstemhe Maschme 3,644,969 2 1972 Guillermin et al 28/72. 14

Apparatebau Ge'sellschaft mbH,

Neumunster Germany Primary Examiner-Louis K. Rimrodt [22] Filed: I Dec. 30, 1971 Attorney, Agent, or Firm-Michael S. Striker [21] Appl. No.: 214,238

[57] ABSTRACT I 1 A crimping chamber is provided having an axially Foreign Applicafion Priority Data spaced inletand outlet and intermediate the same ra- Sept. 6, 1971 Germany 2144479 dial venting ports. A filamentary material to be Y I crimped is entrained and inserted into the inlet of the [52] US. Cl 28/72.", 28/72.12, 28/7214, chamber with a stream of hot fluid which. upon entry I 28/75 WT into the chamber, becomes vented through the venting [51} Int. Cl ..D0 2g1/20 ports. Into the chamber-in the region of the outlet [58] Field of Search 28/].3, 1.4, 72.11, 72.12, there is admitted in counter-flow to the filamentary 28/7214, 75 WT; 226/97; 34/23 material a stream of cool gas which also subsequently vents through the outlet ports, and admitted into this [56] References Cited stream of cool gas is a liquid to be finely dispersed UNITED STATES PATENTS therein- 3,669,328 6/1972 Castelli 226/97 7 Claims, 3 Drawing Figures i T I 7 1: z

METHOD OF CRIMPING OF FILAMENTARY MATERIALS CROSS-REFERENCE TO RELATED APPLICATION A related application was filed on Dec. 14, 1971; it is copending under Ser. No. 207,826.

BACKGROUND OF THE INVENTION The present invention relates generally to the crimping of filamentary materials, and more particularly to a method of effecting such crimping and to an apparatus for carrying out the method.

In the aforementioned copending application have already disclosed an improved crimping method for the crimping of filamentary material, including but not exclusively of filamentary material composed of synthetic plastics.

That method provides a crimping chamber having an axially spaced inlet and outlet and intermediate the same having a plurality of radial venting ports. A stream of hot gas is utilized to insert filamentary material to be crimped into the inlet of the chamber and as the hot gas enters the chamber it vents through the venting ports. As a result of the venting the filamentary material is more readily deformable (crimpable), especially if it is of a synthetic plastic, andas a result of the venting of the hot gas as it enters the chamber the incoming increments of the filamentary material lose velocity and tend to resist the newly entering increments of filamentary material which still move at the higher speed imparted to them by the stream of hot gas exteriorly of the chamber inlet. This push exerted by the successive filamentary material increments upon those already in the chamber and having undergone deceleration, causes the increments in the chamber to assume a wavy configuration, that is to become crimped, forming a plug of such crimped material in the chamber.

In counterflow to the fiamentary material in the chamber there is admitted a stream of cool gas into the chamber in the region of the outlet thereof, so that the cool gas contacts the filamentary material in the chamber. Preferably the filamentary material which has been crimped in the chamber is withdrawn through the outlet of the chamber and the incoming cool gas, so that the crimp becomes more or less fixed and withdrawing (with the concomitant tensile stresses upon the filamentary material) becomes possible without destroying or damaging the crimp.

The temperatures at which the hot gas and the cool gas should be kept, that is both temperature ranges and preferred temperatures, are fully disclosed in the aforementioned copending application to which reference may be had for further details. It is also explained in that application that the disclosed method and apparatus provide for a substantially more uniform (and therefore desirable) crimping of filamentary material because precisely defined conditions exist in the crimping chamber.

However, it would appear that further improvements are still possible and, of course, desirable.

SUMMARY OF THE INVENTION It is, accordingly, a generalobject of the invention to provide such further improvements.

More particularly it is an object of the invention to provide a still further improved method of crimping filamentary materials.

An additional object of the invention is to provide an improved apparatus for carrying out the novel method.

In pursuance of these objects, and of others which will become apparent subsequently, one feature of the invention resides in a method of crimping filamentary materials which, briefly stated, comprises the steps of providing an enclosed space having axially spaced inlets and outlets and radial venting ports intermediate the same. The filamentary material! to be crimped is entrained and inserted with a stream of hot fluid into the inlet, so that the material advances towards the outlet and becomes crimped whereas the hot gas vents radially through the venting ports. Into this space there is admitted, in the region of the outlet and in counterflow to the advancement of the filamentary material, a stream of cool gas for subsequent venting through the venting ports. In accordance with the present invention there is further admitted, and in particular into the stream of cool gas, a liquid-usually but not necessarily water-which becomes finely dispersed in this stream of cool gas.

The present invention provides for a particularly effective cooling of the crimped filamentary material and for a vastly improved fixing or setting of the crimp in the filamentary material. Thus, withdrawing of the filamentary material through the outlet does not in any way effect disadvantageously the crimp which has been produced in the filamentary material. This is quite in contrast to the prior art where the filamentary material could not be withdrawn but had to be either pushed out with the hot gas or had to be permitted to be pushed out by the force exerted by newly entering filamentary material, so that the plug of expelled filamentary material would fall into a suitable receptacle provided for this purpose at the outlet end of the chamber and would there be permitted to cool before it could be withdrawn for winding-up on a bobbin or the like. Even in the aforementioned copending application the crimp produced in the filamentary material in the chamber is not as reliably protected against disadvantageous influences resulting from withdrawal directly out of the outlet of the chamber, as is the case in the present invention.

In particular, the liquid which is admitted into the stream of cool gas will at least in part become vaporized whereby the temperature of the stream of cool 'air is further decreased and its specific heat increased, re sulting in an enhancement of the cooling effect. The cooling effect is, furthermore, substantially improved if the liquid is present in part in vapor form in the cool gas stream.

It has additionally been observed that in part the liquid becomes absorbed by the filamentary material itself, tending to improve the characteristics of the same.

The invention also provides for dissolving in the liquid any desired solids, for instance coloring matter. In this manner the crimped filamentary material can already be colored or treated with other suitable materials during the crimping, and in particular it is possible to use this effect for applying relatively small quantities of coloring matter to the filamentary material during crimping in order to mark and characterize the mate rial (color-coding) for further operational steps. Of course, instead of coloring matter other suitable matter can be dissolved in the liquid, for instance for treating the filamentary material as desired.

The novel invention also provides for an improved apparatus for crimping further filamentary materials, and this apparatus comprises first means surrounding a chamber having axially spaced inlets and outlets and radial venting ports therebetween. Second means are provided for entraining and inserting with a stream of hot fluid into the inlet a filamentary material to be crimped, so that such material advances toward the outlet and becomes crimped whereas the hot fluid vents radially through the venting ports. Third means admits into the chamber in the region of the outlet and in counterflow to the direction of advancement of the filamentary material, a stream of cool fluid for subsequent radial venting through the venting ports. Fourth means admits into the stream of cool fluid a liquid for fine dispersing of the latter in the stream of cool fluid.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of the specific embodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a somewhat diagrammatic partial longitudinal section illustrating an embodiment of the novel apparatus;

FIG. 2 is a section on line IIII of FIG. 1; and

FIG. 3 is a section taken on line IIIIII of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Discussing the drawing now in detail it will be seen that the novel apparatus, with which the novel invention can be carried into effect, comprises a tubular member 1 into which a crimping chamber 5 is inserted. The crimping chamber 5 is configurated, as particularly clearly evident from FIG. 3, of a plurality of lamellae 6 which are mounted at their opposite ends in annular mounting members 7 and 8; these lamellae 6 are in form of elongated strips, for instance of a suitable steel or the like, and their inwardly directed edges (note that they are arranged in star-shaped configuration) define between themselves the chamber 5-, and successive ones of the lamellae define with each other radially directed longitudinally extending venting ports 2 whose cross-section increases in radially outward direction.

At opposite axial ends the tubular member 1 is provided with an inlet nipple 3 for hot fluid, usually hot gas such as air, and an inlet nipple 4 for cool fluid, usually cool gas such as air. A valve 24 permits the supply of hot fluid to be throttled or stopped, and the conduit connecting the supply with the inlet nipple 3 is provided with a pressure indicating device and a thermometer 27 as well as a regulating valve 26. The operation of these various devices, and the manner in which the supply of hot fluid and the temperature thereof can be kept constant in automatic manner with the aid of these devices, has been disclosed in the aforementioned copending application to which reference may be had for details.

Similarly, the conduit communicating with the inlet nipple 4 for cool fluid is provided with a valve 28 by means of which the supply of cool fluid can be throttled or terminated, a pressure indicating device 29, a thermometer 31 and a regulating valve 30. Again, details for the operation of these devices analogous to that set forth above with respect to the devices for controlling the flow and temperature of the hot fluid, can be obtained from the aforementioned copending application.

There is further provided a liquid nozzle 32 which communicates with the conduit for the stream of cool air, upstream of the inlet nipple 4 as seen with respect to the direction of flow of the incoming cool fluid or air. A reservoir 34 for liquid (usually water) is provided, a'nd advantageously is located at a high enough level so that gravity feeding of liquid to a nozzle 32 is obtained. Interposed between the reservoir 34 and the nozzle 32 is a regulating valve 33 for regulating the quantity of liquid flow, and liquid which enters through the nozzle 32 into the conduit for the cool gas becomes finely dispersed in the stream of cool gas and to the extent possible will vaporize therein.

I-Iot gas admitted via the inlet nipple 3 will radially vent through the ports 2 in the portion of the chamber 5 which is the upper portion in FIG. 1, and cool gas admitted via the inlet nipple 4 (and containing the admitted liquid) will radially vent in that portion of the chamber 5 which in FIG. 1 is the lower portion.

A supply tube 9 is provided communicating with the inlet of the chamber 5 and having in turn an inlet end which is wider and which is provided with gas conduits l0 communicating with the nipple 3. The tube 9 carries a conduit 11 for the filamentary material, and the upper part of the tubular member 1 is surrounded by a housing 12 which is filled with a thermally insulating material 13 to reduce thermal losses as much as possible.

Communicating with the outlet of chamber 5 is an outlet tube 14 for the crimped filamentary material, configurated analogously to the tube 9 but having preferably a larger diameter than the inner diameter of the chamber 5, which inner diameter of the chamber 5 in turn corresponds at least substantially to the inner diameter of the tube 9. The reason why the inner diameter of the tube 14 is preferably larger than that of the chamber 5 and of the tube 9 is that it is desirable for the flow speed of the hot gas in the tube 9 to be high because the hot gas of course is used to insert the filamentary material into the chamber 5, whereas a high flow speed in the tube 14 with which the nipple 4 communicates and into which it discharges the cool gas is not desired. Located in a portion of the tube 14 which is spaced from the outlet of the chamber 5 and provided with gas channels 15 for the stream of cool gas, is a filamentary material outlet nozzle 16 which is known to those skilled in the art.

The lower part of the tubular member 1, and the part surrounding the chamber 5 is surrounded by a housing l7, 18 so as to form an outer chamber about the chamher 5. A suction conduit 19 communicates with this outer chamber and interposed in this suction conduit is a pressure indicating device 21 and a regulating valve 22; the suction conduit communicates also with a ventilator 23 so that gas vented through the ports 2 can be withdrawn from the outer chamber via the suction conduit [9. ln a manner which is fully disclosed in the aforementioned copending application, the values measured by the device 21 serve to control the operation of the valve 22 and thereby to control the quantity of gas which is withdrawn through the suction conduit 19, in order to permit maintenance of the pressure in the outer chamber at a constant level. It is in fact preferred, but not necessary, that this pressure be maintained somewhat below the ambient atmospheric pressure to facilitate venting through the ports 2.

The filament or filamentary material is identified with reference numeral and it will be seen that it is sucked into the tube 1 by the effect of the stream of hot gas flowing through the tube 9. In the tube 9 it is heated by contact with the hot gas and inserted into the chamber 5. As soon as the hot gas enters the chamber 5 it will immediately vent radially outwardly through the ports 2, and the velocity loss accruing as a result of this to the increment of filamentary material which has just been inserted into the chambers, combined with the resistance exerted to its advancement by the cool gas which enters in the region of the chamber outlet end, causes the filament to be retarded and to become crimped by the push exerted by the following increment. In crimped configuration the filamentary material then passes through the chamber 5 and has its crimp fixed by the cool gas in which the liquid is dispersed.

The crimped filamentary material with its crimp set is withdrawn in this condition through the tube 14, having to pass through the incomingcool gas which moves in counterflow to it, and the cooling as a result of the liquid content of the cool gas is particularly effective during such movement before the filamentary material is withdrawn in crimped condition'through the outlet nozzle 16.

Because preferably the quantity and temperature of the hotand cold gases admitted into the chamber 5 are maintained constant, and because of the constant gas pressure maintained in the outer chamber which is surrounded by the housing portion 18, the forces acting upon the filamentary material in the crimping chamber Sare very even and uniform, and a corresponding even and uniform crimping of the filamentary material is obtained. This crimping israpidly andeffectively fixed or set by the cool gas, and in particular by the fact that the cool gascontains the liquid which has been admitted into it.

The quantity of liquid admitted into the stream of cool gas depends upon the requirements of a given situation. If for instance a particularly even moistening of the filamentary material is desired, then only so much liquid is admitted into the cool gas that the stream of cool gas becomes saturated with the liquid vapor; in that case the liquid is available in vaporform as it contacts the. filamentary materiaLOnthe other hand, if larger quantities of liquid are to be. applied to the filamentary material, desirable or even necessary in many instances for the further processing of the filamentary material, or if a solution for instance of coloring matter is to be applied to the filamentary material, thenthe amount of liquid admitted into the stream of cold gas is selected so high that it is carried along in formof droplets in the stream of cool air, forming a fog therein.

if the outer chamber surrounding the chamber 5 is to be maintained at sub-atmospheric pressure, then it is advantageous to maintain it at a pressure of between substantially 0.01 0.1 atmospheres.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the types described above.

While the invention has been illustrated and described as embodied in the crimping of filamentary materials, it is not intended to be limited to the details shown, since various modifications and structural may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific'aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims:

1. Method of crimping filamentary materials, comprising the steps of providing an enclosed space having an inlet and an axially spaced outlet and radial venting ports intermediate the same; entraining a filamentary material to be crimped with a stream of hot fluid and inserting the filamentary material into said inlet so that such material advances towards said outlet and becomes crimped within said enclosed space, whereas said hot fluid vents radially through said venting ports; admitting into said space, in the region of said outlet, a stream of cool gas for contact with and initial counterflow to the direction of radial advancement of the crimped filamentary material, and for subsequent venting through said ventingports; and admitting liquid into saidstream ofcool gas for dispersal therein and for enhancingthe cooling effect thereof on the crimped filamentary material, whereby to uniformly cool the latter in said space prior to withdrawal thereof from said space through said outlet.

2. Method as defined'inclaim 1, wherein said liquid iswater.

3. Methodas defined in claim 1, wherein the step of admitting said liquid comprises admitting the liquid to said stream of cool gas in a quantity which is smaller than the amount required for saturating said cool gas with liquid vapor.

4. Method as defined in claim 1, wherein the step of admittingsaid liquid comprises admittingthe liquid to be crimped with a stream of hotfluid and advancing the former at a first speed in an elongated path in direction from an inlet to an outlet thereof; venting the hot fluid radially of said path to reduce said first speed to a lower 8 l fect thereof on the crimped filamentary material, whereby to uniformly cool the latter with attendant setting of the crimp in the filamentary material; and withdrawing the filamentary material having the set crimp through said outlet. 

1. Method of crimping filamentary materials, comprising the steps of providing an enclosed space having an inlet and an axially spaced outlet and radial venting ports intermediate the same; entraining a filamentary material to be crimped with a stream of hot fluid and inserting the filamentary material into said inlet so that such material advances towards said outlet and becomes crimped within said enclosed space, whereas said hot fluid vents radially through said venting ports; admitting into said space, in the region of said outlet, a stream of cool gas for contact with and initial counterflow to the direction of radial advancement of the crimped filamentary material, and for subsequent venting through said venting ports; and admitting liquid into said stream of cool gas for dispersal therein aNd for enhancing the cooling effect thereof on the crimped filamentary material, whereby to uniformly cool the latter in said space prior to withdrawal thereof from said space through said outlet.
 2. Method as defined in claim 1, wherein said liquid is water.
 3. Method as defined in claim 1, wherein the step of admitting said liquid comprises admitting the liquid to said stream of cool gas in a quantity which is smaller than the amount required for saturating said cool gas with liquid vapor.
 4. Method as defined in claim 1, wherein the step of admitting said liquid comprises admitting the liquid to said stream of cool gas in a quantity which is larger than the amount required for saturating said cool gas with liquid vapor.
 5. Method as defined in claim 4; further comprising the step of admixing with said liquid dissolved solid matter.
 6. Method as defined in claim 4; further comprising the step of admixing coloring matter with said liquid.
 7. A method of crimping filamentary materials, comprising the steps of entraining a filamentary material to be crimped with a stream of hot fluid and advancing the former at a first speed in an elongated path in direction from an inlet to an outlet thereof; venting the hot fluid radially of said path to reduce said first speed to a lower second speed, and concomitantly crimping the filamentary material; directing a stream of cool gas on said crimped filamentary material for initial counterflow to said direction and for subsequent venting radially of said path; admitting liquid into said stream of cool gas for dispersal therein and for enhancing the cooling effect thereof on the crimped filamentary material, whereby to uniformly cool the latter with attendant setting of the crimp in the filamentary material; and withdrawing the filamentary material having the set crimp through said outlet. 